Control system for controlling the temperatures of individual enclosures



2,660,407 ATURES Nov. 24. 1953 T. J. LEHANE CONTROL SYSTEM FOR CONTROLLING THE TEMPER OF INDIVIDUAL ENCLOSURES 3 Sheets-Sheet l Filed Dec. l, 1949 INVENToR. el@ @lem BY 'Filed DeC. l. 1949 CONTROL T. J. LEHANE 2,660,407 SYSTEM FOR coNIRoLI-.ING THE TEMPERATURES 0F INDIVIDUAL ENcLosuREs 3 Sheets-Sheet 2 Nov. 24, 1953 T J EHANE 2,660,407

CONTROL SYSTEM FOR. CNTROLLING THE TEMPERATURES OF INDIVIDUAL ENCLOSURES Filed DeG. l. 1949 3 Sheets-Sheet 3 FLOOR EAT CON TZQL Patented Nov. 24, 1953 CONTROL SYSTEM FOR CONTROLLING` THE TEMPERATURES OF INDIVIDUALv ENCLOSURES Timothy J. Lehane, North Riverside', 1111assignor to Vapor Heating Corporation, Chicago, Ill., a corporation of Delaware Application December 1,l 1949, serialNo. 132,025A

1o claims. (o1. 257-3) This invention relates to an improved control system for controlling the'temperature of individual enclosures arranged in a group. l

' A principal object of the present invention is to provide an automatic control system of the above character which is particularly suitable for use in connection with temperaturev altering apparatus composed of means for delivering tempered air (heated or cooled) into the several enclosures of a group including heating and cooling apparatus serving all enclosures of the group and individual air conditioners for each enclosure. Another object is to provide, in a control system of the above character, control elementsresponsive to temperatures affecting the several enclosures as a group and other control elements responsive to the temperatures of the individual enclosures; and also to provide means for adjusting the functional setting of certain of the temperature responsive elements, which adjustment serves to proportionately vary the adjustment of another control element of the system.

Specifically the invention contemplates a control system including control thermostats responsive to the temperatures of individual enclosures of a group and one or more control thermostats vresponsive to the temperature components affect- Yadjusting means, for certain of said thermostats,

includes connections for automatically adjusting the temperature setting of the thermostat means which responds to the temperature components affecting the group of enclosures.

.According to the present invention, the controls are interconnected to control temperature altering apparatus comprising means for tempering air for delivery into a plurality of enclosures, means for heating the air immediately before it is introduced into the individual enclosures of the group, and means including heat radiator elements, for example floor radiators, each serving a plurality of said enclosures and adapted to de.- liver heat directly into the enclosures associated therewith to supplement the heating functions of the other air heating elements.

The control system includes an outside thermostat adapted to function at a predeterrninedv outside temperature to makeL cooling effective, when the inside temperatures of the .enclosures are such as to make cooling desirable. y

When the cooling' apparatus is functioning, the heating medium is shut off from the floor radiators and from the main air heater,- but heating medium remains available for the booster heaters, since it may be desirable-to raise the temperature of theair delivered into a selectedrenclosure during both the heating and cooling cycles of the system.A

The main'air tempering apparatus (both heating and cooling) are controlledv by means including heating and cooling control f thermostats located in a main delivery duct so as to respond to the temperature of the air within said duct.

The means for controlling the floor radiators includes a thermostat responsive to the temperature of the wall panel defining one side wall Aof each enclosure of a group of such enclosures. The several booster heaters are controlled by means including separate thermostats located in the individual enclosures served by an associated booster heater. The last mentioned thermostats are provided with auxiliary electrical heaters and means for varying 'the heating effect thereof so as to adjust the functional setting of the thermostats in'accordance with the Wishes of the occupant. `rThe said adjusting means also includes connections with a similar heater for the iioor radiator control thermostat whereby the iioor radiator thermostat is automatically proportionately adjusted in relation to the adjustment of theindividual enclosure thermostat. The other thermostats, except the outside thermostat, are provided with electrical heaters which are so connected in the control system as to produce cycling operations of the thermostats when the temperatures in their various localities come within a selected range of their temperature setting.

The invention is illustrated in the accompanying drawings in connection with a railway car sub-divided into separate compartments, but the specific illustration is for the purpose of convenience only and should not be regarded as a limitation.

In the drawings:

Fig. 1 is a plan view in section illustrating a railway carsub-divided into a plurality of separater compartments and illustrating main and branch air ducts for delivering tempered air from a common source into the several compartments.

Fig. 2 is a Vertical longitudinal section through the car construction shown in Fig. 1 and'illustrating the arrangements of the several temperature altering means.

`Fig. 3 is a transverse vertical section through the car illustrating the position of the air supply and circulating ducts associated with the several temperature altering apparatuses.

Fig. 4 is a fragmentary view of a booster heater for adding heat to the air delivered into the individual compartments of the car.

Fig. 5 is a longitudinal sectional View of one of the floor radiators installed the said car, and

similar series of separate compartments desig-f' nated B along the other side.V .AA-central aislewC extends lengthwise of the car 'hetweien'thetwo groups of compartments. A main air duct D extends substantially the full length of the car and is provided at spaced locationswith'branoh ducts Ef--E' which lead fronthe inain duct'int the several compartments of the groups A and B,

respectively. At one end ot the mainiduct "D2- an electrically operated blower H is provided which serves to draw aiixfrom the outside of the oar, for example the vestibule I2, and force it into 'the' vairduct D; The air is 'passed ythrough ter from the air before it is delivered into the main Iduct D; APositioned the mainair duct is 'a primary apparatus for supplying tempered air vincludingan airheatin'g element i4 and a cooling element +5, eac'h 'ofwvhichmay be selectively enervg'ized Aby the-controls'ystem hereinafter 'described to heat -or'cool the aiijjto a desired temperature Vbefore it `is introduced 'into' the Vmain duct- D. The ai-r "thefmainduct is maintained at a uniform vtempera-ture but somewhat lower than the temperaturewhichjwould beV normally required to 'provide Vthe desired comfort in the several compartments of the car; For example, during the yheating cycle `of the system `the air in the main duct maintained Vat 'temperatures of 60 to 65 Fahrenheit. Theftempera'tureof the airis'raised 'by means of 'booster 'heaters t6 'located in the branch ducts Ej-E jwhich lead from the main Aduet D into each -or 4the several compartments A 4or B, as-the case-may be'. The effectiveness ofthe booster Aheaters H5 are individually 'controlled 'by means of -control 4mechanism responsive to `the temperature of 'theli'ndividual compartments Aassociated -with `the ibooster heaters.

During the heating cycle, lparticularly lwhen `the outsideternperature stands'below 40'Fahrenheit, '-heat is lte'livered *to -floor radiators "iT-IT which are lr'neferablyV A located kat opposite sides of fthecar andextend-sbstantially fromjend to end of the car. "Ehe-said'radiaitors IlA-TT' tare. enclosed jin vsuitable)grills 'f8-llt* near the floor level of the car'so that'a'nportion Aof the heat from the 'radiators 'will pass-directly into 4each .of 'the 'several compartments. The g'rills also communicate with passages designated T9-T9 'formed 'in the side wall structure of the car andhavin'g outlet openings -20 throug'hthe window 2 l of the-car. A'porti'on ofthe 'heated air passing over the oor 'radiators [1 -T1 will 'move up- Iwardlythrough `the. passagesfl'S-l Vanrl'be discharged 'from openings lll-2U' across 'the Aglass pane-of theoarwindows. The wall structure between adjacent windows provides passages "22- 'Z2' which Adirects a portion of 'the air from the Hoor 'radiators to -'mitle't openings 23-23 located adjacent the top of the car windows (see Figs. 2

3). y Y 'The floor radiators are preferably of the inner feed 'type'comprising an outer pipe 24 connected at one end tothe outlet chamber -.of an admission valve structuren. The 'pipe 2l extends'substantially 'the `full length .of .the car and is vprovided 4on its .outer surface withheat dissipating #fins "21. 'Heating medium. is delivered into lthe radiator from the inlet pipe 28 through a normally open but energized closed solenoid control valve 29 into the valve inlet chamber 3B. The said heating medium thenpasses through a feed pipe Si isslocatedwvithin and `concentric to the outer pipe 24 of the radiators. 'The heating medium is discharged from the inner pipe at its louter end and flows rearwardly toward the valve structurethrough'ithe outer pipe 24 and is disrchargedtmough the drain pipe 32.

'llhemainkheaiting element I4 and the cooling element .l5 for supplying tempered air to the viriafinduct D arecontrolled by thermostats located .'inthe .duotlD The thermostat for controlling the heating element I4 is designated 33 and is preferablysetto-function at 60 F. The cooling control thermostat is designated 34 and is likewise positioned in the main duct D. It is preferably set to function at 76 F. The particular setting is merely 'a matter of conveniencev and is not'critical. The functioning of the floorradiators are controlled Vby means including a Ythermostat l1 which preferably respond'stothe tempera'ture of the side Wall panel. Only one of these 'thermostats 'is shown for controlling 'the door radiators at opposite sides of the car.

The-ibooster-heaters i6 Aare of the conventional honeycomb type and 'are supplied with heating medium, for 'example steam, through an electrically controlled admission 4valve 36, the steam berngtaken from thetrain'line 3-1'throughibranc'h 'supply'line '38 to-supply each ci the severalbooster heaters lili. "The valve -is normally closed by a spring 3S and is opened yby the energization of a solenoid 40. The condensate is discharged "throug'ha Ydrai-n 4i yleading from each of the several lboosterheaters to 'a conventional steam trap 42.

Thesolenoid A4i! of veach lof 'the several booster heatervalves is controlled ny-means including a thermostat located within each of the several compartments. vThe'therrri-ostats located in compartments A, forpurpose of convenience, lare des- `'gnated A4l and vthe thermostats located Yin 'the compartmentsBare designated n4 ls. rIhese thermos'tats are" `responsive to thetemperature of the compartment 'in which Athey are located. Each of the -said -thermostats 4 I-4I is `provided with an electrical heater 421-42 which is connected "-to'a sourceof electrical energy through a poten- "tiometer 43.-43', whereby the 'temperature 'set- "tings Aof Jthe thermostats "41 '4 1"' may 'be individ- -ually adjusted "to any lsuitable temperature 'between 65 and 80'. vrFor example, whenithe potentiometer arm 44-4'4" 'is positioned toinclude 'the total-resistance of thevpotentiometer, the associated thermostat 141 or 41" as `the case maybe, '-Will have 'a functional setting of 80' F. .and when thepotentiometer arm is movedso as to eliminate all resistance the thermostat will 'have ,a .temperature setting of '65 F.

`TIie.solenoid valve 28 .for controlling theheating medium to a iioor radiator is normally held its lopen position'by'means of a spring Y45 .and is closed Yby the energization of the solenoid 46-46. Inasmuch as both -oor radiators are Ycontrolledby one `thermostat 41 the valvefsolenoiis .4S-'4B' are connected in parallel. The

' 'thermostat 1 is provided with an electrical heater '4B which is :connected through a potentiometer K adapted to be controlled bythe porter or other authorized persons of the train crew to vary Ythe temperature setting of the `radiator control `thermostat 41. The energizing circuit .for .the .said .electrical heaters 48 are valso con nected, through metering resistors 49-49 (Fig. 6) with each of the potentiometers 43-43'- The metering resistors 15S-49', as herein illustrated, have a resistance value of 1 Fahrenheit when the potentiometer arm is moved to a position to exclude all resistance. However, the effect of said metered resistors are proportionately reduced when the potential is decreased by shifting the potentiometer arms 44--44 in a direction to introduce greater resistance.

Referring now to the circuit diagram of Fig. 6: In addition to the control thermostats previously mentioned the circuit includes an outside thermostat 50 which is normally set to function at 40 F. This thermostat controls the energization of a relay F provided with three bridge arms 5|, 52 and 53.` The bridge arm 52 is included in a circuit leading to the upper contact of duct thermostat 33'which, as before indicated, is normally set to function at 60 F. The bridge arm 53 leads to the upper contact of thermostat 41 for controlling the energization of the iloor radiator admission Valve solenoids 46-46. The several control elements are shown in the positions which they will assume when the outside temperature is below 40 F. and the temperature in duct D is below 60 F. and the temperatures in the individual enclosures a are below the temperature settings of thermostats 4| and the individual temperatures within the compartments B are at orfabove the temperature settings of thermostats 4|'. Under the assumed conditions, the main switch 54 is closed and thereby closes a circuit through the blower The blower normally operates continuously during the operation of the system and is energized by a circuit leading from the positive line` 55 through conductor 56, blower I| and conductor 51 to the negative line 58. Inasmuch as the outside temperature is below 40 F. the mercury column of thermostat 50 stands below the upper contact of this thermostat. Consequently the relay F is de-energized. When the relay F is in its deenergized position and the `duct thermostat 33 is calling for heat the relay G, associated with duct thermostat 33, is energized to close an electric circuit through solenoid valve 59 to admit heating medium to the main heater I4. The energizing circuit for relay G leads from the positive line 55 through wire 60, bridge arm 52 of relay F, wire 6|, resistor 92, and wires 63 and 64 through the solenoid coil 55 of relay G and thence through wires 66, 61, resistor 6B and wire 69 to the negative line 53. The energization of relay G closes its contacts 19 so as to close an energizing circuit through the solenoid admission valve 59 for controlling the supply of heating medium to the main heater I4. This circuit leads from the positive line through wire 1|, closed relay contact 10, wire 12, solenoid valve coil 59 and wire 13 to the negative line 58. Simultaneously with the opening of the admission valve 59 to deliver heating medium to the main heater I4 a circuit is closed through an auxiliary heater 14 for adding 2 of heat to the thermostat 33. This heating circuit leads from the positive line 55 through wire 15, closed contact 16 of relay G, wire 11 and metered resistor 18 and wire 19 to the electrical heater 14 and thence through wire 80 to the negative line 58. When the temperature of the air within the main duct rises to 58"l the 2 of heat added to the resistor 18 will be sufdcient to close the upper contact of the thermostat 33. In'such case the electrical current luy-passes the solenoid 65 of relay G and passes directly from wire 63 through wire 61 through;

the mercury column thermostat 33 and therebyresults in de-energizing relay G whereupon 'the contacts 10 and 15 move to their open position.l

This condition is maintained only momentarily since the opening of the contact 16 de-energizes the electrical heater 14, whereupon the mercury column of thermostat 33 will recede ,to

a position below its upper contact so as to effect re-energization of the relay G. This cycling oper-1` wire 8|, de-energized closed contact 53 of relayv F, wire 82, resistor 33 and wires 56 and 85 through solenoid coil 8| of relay H and thence through wires 85, B1, resistor 83 and wire 89 to the negative line 5S.

fore the actuating solenoids 46-46 of the floor heat valves 29 are de-energized to permit the valves to open. The functional setting of thermostat 41, may be varied by varying the intensity or" the energizing current supplied to its heater $8. The intensity of this heating current is controlled by means of a variable resistor 92 under the control of the porter. The normal heating current to heater 48 therefore leads from positive line 55 through wire 9|, variable resistor 92 ofV potentiometer K, potentiometer arm 93, wire 94, metered resistor 95, having a resistance value of 15 F., wire 96 to heater 48 and thence through wire 91 to negative line 58. With the illustrated adjustment of variable resistor K sufficient heat is applied to thermostat 41to establish a functional setting of 70 F. When the relay H is energized, as herein indicated, additional heat (approximately 2) is added to the heater 48v to produce cycling operations. This heating circuit leads from positive line 55 through wire 98, closed contact 99 of relay H, metered resistor |09 and wire |0| to wire 96 and thence through the heater coil 48 and wire 91 to the negative line 53. This last mentioned heating circuit is effective only momentarily when the temperature of the side wall panels stands within 2 of the functional setting of thermostat 41. When the temperature of the wall panels is suflcient to hold the mercury column of thermostat 41 in engagement with its upper contact the electrical current iny wire 84 is directed through the mercury column to wire B1 and thereby by-pass the relay coil 8| so as to release the relay. As soon as the temperature of the Wall is suicient to maintain the thermostat 41 closed without the additional 2 of heat supplied through resistor |99 the relay H is released so as to move its contact 99 to its closed positionand thereby establish an energizing Ycircuit, through the valve solenoids 45-46 to shut off the supply of heating medium to the floor radiators. The energizing circuit for said solenoids 45-46 leads from positive line 55 through wire |02, closed contact of relay H, wire |93 through the solenoids 43-46 `and wire |04 toA the negative line 58.

The thermostats 4| and 4|' for continuing the In the energized position of relay H, its bridge arm 90 is opened and there-l effectiveness of itheehooster heaters lsiare locatedf withinithelindividuall enclosures-sov asito-v be responsiverA to lthe temperature -therein:- inasmuchA asthefl therrnostats and their associated relays '.L-I-r are oi,I likeE construction; only two=of said tlierrnostatsI and.: relays are illustratedA inf. the@ wiring-diagram; In thisuconnection'the-thermostatl will loe described andcorrespondingnumzm ers?A with'V the*y primel exponenttwill identify." coreVV responding yparts .fonthermostat 4 i iv Thethermostat' 4 g as:` previously` indicated, is: providedwith an electrical heater 142ii which is? energized by a circuit;leading'fromk positive-line 55`fthrough2wire? |05.l variable. resistor 43; vWire-i 06 and metered resistance 01,' having: a.. maximum vaiueof f 15, wire-i |18-,l electricallheater 42 and Wirev |0`9"to thefnegative line' 58E Thevariahle resistor 43` makes it' possibl'et to` adjust the: temperature' setting ofthermostat 4| from-65 to80". Fonexa ample; whenlall oftheresistance 43is included in i'il'iercircuit theA thermostat '4| Willi function at 80; When allv off theresistance t3L is'Y removed from the circuit the thermostat will function at` 65, the amount of electric current supplied tor the heater 42l|oeingL then determined-by: thevalue ofthe resistor' |01; Aresistor 49, having al maxi-r mum'value-of 1 of heat, is connected in` theheateing circuitfcontrolled by the potentiometer t3 *and* leads to'thef electrical heater 48 oftheiioor radi-- ator thermostat 4-'|.\` Consequently-when allv of'` thei` resistancekoif potentiometer 432? is excluded from-the heatingcircuit for thermostat 4| so thatthelatterwill function atv 65F, l" ofaddietional heat is added: to the-'floor'. radiatorA control thermostat` 41A4 so -a'stov adjust thisL thermostat in relation to'theflower temperature settingof' the individual'V roonrthermostat 4|-, They heatingcircuit of# each roomv thermostat 4|-41 supplies additionalv heating current throughv resistors4 49"-49 tothe heater 48- ofthe-said floor radiator thermostat', each of the said resistors i5-49' heing` connected into aconductor H03 whichA is joined" at' |I| with the' Wire 5S= leading tolthe' heater Miof thermostatfl.l Itwill bevseenthere forethat the thermostat 41- is adjustedfinfrelation to the temperature-settings oi` all 1 room thermo;r stats: In the '-presentLillustration it*- Willil loe-seen' that the" movable arm 44'- of the potentiinneter-l associated" with thermostat' 4|' is -adjustedso as'- to'remove vall lof thefresistance- 43'i Inf such casethe thermostat 4| receives the lfull i5 set-down and=therefore will function -at- 65Y`Ff andfonef'ull degree" of: heatl` is added byf resistorf 49": tothe heater: 48; of'Y the floor radiator tlierrnost'ati'A 41l whereasfthe'arm' 454 oi-'the potentiometer-associe ated'with thermostat 4|1 is a'diustedto addzsu'-V cient resistance inthe heaterl circuit, whereby said thermostat 4| will'fun'ction'at approximately' 70. Consequentlyl the electrical current sup'- plied to heater'48 through-resistor 451 is "less-than 1"; The relay-'Ifis'under the controlfof thermo`` statu. Whenthe thermostat' callslfor'heat the' relay'is'energized lov-acircuit vleading from posi-4 tive' linev 55 through' wire H2?, resistor H3" and" wires H4 and H5 through solenoidl coil` H 6` andthence through vviresA H1 and H8, resistor H5- and Wire |to the'negativelinef-SS The ener-- gization of'l relay I closes an energizingi circuit'- through the solenoid* to open theadmission:

valve 38 and therebyV deliverl heating medi'urnto' the booster heater |62 This energizingI circuit*- leadsfrom' positive-line through` Wire` |2Ti, relay closedfcontact |22 oi-'rel'ay I; Wire |23?4 valve'sole`x noid 40. and Wire |24 to thel negative iin-e 58;

Si; tioned" energizing: circuitzzadditional; heatngffcurf'e rent is applied to thelv thermostati` heater- 4@ through a. circuit leading fromA the I positive `:line through-Wire |25, closed contact |261Lofrelayl` wire Y i 21; metered resistor 25'; wire 251-' andflW-ire |08 to the heater 42.*.-v andi/hence through` Wiref |091 trrtlie negative line :58; The'resistor' |128 hasaa value2 of approximatelyfZ-Fi Consequently, Whenithe'temperature at thermostat-41' is within- 2 of its functional setting the 2?ofheatuadded' tolthef resistor |28l will closet-thel thermostat'f1 at its upper. contact sofas=to=deenergize the relay I, theelectric current; insuchl case; being passed: directly fromfwiref H4 towire H81: throughv` the mercury column .of thermostat-4 l; The removaloflthe 2f of`heat, hy'virtue of thec rie-energica tion of relayfI, Will'again result in.re-energizing.'4 relayf" I to' momentariiyf energize' solenoid 403 to" open admission valve- 3'6 and thereby admit' al burst 'of' heating mediumk intol `the booster' heater. |6-. This cycling action Will continue until the temperature of 'theenclosureA in which thermo stat 4 |v is located reaches the temperature setting of* thel thermostat. For example,v 'T097A for the thern'lostatY 45| or 65a for the thermostat 4 f.

Reierri'ngvvnow to the control function-ofthe' system-during the cooling of thelenclosureslAfland Wen=tlie outside temperature rises1toA0 F'.' orfhi'gher the outsidethermostat 50isf closedand?l there'n'y-l completes an energizing circuit through` theL actuating solenoid |3l- This energizing-Y cin-'1 cuit? leadsT from positive yline 55' through :wire 2 9i relay# coilf |30, Wire |32,A mercury# columnE offr thermostatl to wire: SSTQand-.thence through re;-J sistor |34l andfwire |35- tothe negative line. 58;' Thei energi'zation of relay` Fopens thecontaotsf 52`and-53Isof as to* deenergize' relays Gfand-I-I- and? therehy Ishutfoiall heat'. to the air heater. lllandf toetheeiloor radiator |1|`|'.' However, heating; medium'- remains available tothe booster-heaters H andi-these'fheaters remain operative lunder theI control-2` of their respective control thermostats iii-41 Theicooling4v apparatus I5 islenergizedby; the closing-'of' relay J which relay-is'under the'c'on-A trol'- off thermostat 34. This thermostat 1 isj nora ma1l`y-= set to function atf'16" FI when nov heat'l isE applied* to itsk electrical heater: |36?. Thisiheater: is=preiferabl`y connected parallelwith .the heatf-f er'40-'of1thevfl'oor radiator thermostat 41 andcona sequently lisproportionately adjusted 'by the Narie able-resistancezBZ ofl potentiometer K. Theheati-f ing Ycircuit for said heater |3Bflleadsffrom Wire' 96? through wire |31 through heater' IBEfJandzthencef through -fwire 38 l-to`` the' negative lline 58. lit-willA` bel observed; therefore; thatv thel cool-ing`x control; thermostatA 31|*v also automatically adjusted: iny relation to the temperatureisettings of theseveral room thermostats since thel current" passingf through: the'several resistors 1491-49! also appliedA heat` to the heater |35 ofthe cooling controlI thermostat '3'4-1. When" the temperature in `duet'D? reachesthe functional setting" of: the cooler con-#1 trol` thernfiostat'` 34S the said' relayA J'. isenergized hva-circuitz leading from positive 'line' 55l'through wire |39, energized closed contactV 5 if ofV relay: F; Wirei. |40, resistor` |4| toAY the` upper: contactzo thermostat 34" and thence through; the'.A mercury column; of" the thermostat'E tolvvire' |42; solmoidi i |43" of'i'elay J andiwire' |44?.totheinegativealine;

58'. The energization. ofirelayl .Ticloses ansehen-i gizing circuitthroughf the: coolingmechanism; cl'uding vthe compressors; valves, etc.; forl'supplye' ingacoolant toithecooler: 5.u Thefzcooling mechesimultaneously with theclosing-fofthelast m'en- T5.' anismisfof conventionalconstructiomanditlflereVA fore is not shown in the present application. The energizing circuit for the cooling mechanism leads from the positive line 55 through wire |45, a closed contact |46 of relay J, wire |41, cooling mechanism and wire |48 to the negative line 58.

I claim:

1. In combination with apparatus for influencing the temperatures within a plurality of enclosed spaces collectively, means including a thermostat responsive to a predetermined temperature for controlling the effectiveness of said apparatus, means for adjusting the functional setting of said thermostat, individual temperature altering apparatus associated with each of said enclosed spaces, means including a plurality of individual thermostats responsive to the temperatures of the separate enclosures for controlling the operation of said individual temperature altering apparatus, manually operable means for separately varying the functional settings of said individual thermostats, and means separately associated with each of the several manually oper-, able means and operable both individually and collectively to adjust within a prescribed limit and in proportion to the adjustments of the individual thermostats, the temperature setting of the thermostat for controlling the first mentioned temperature altering apparatus.

2. In combination with a primary air heater for supplying tempered air to a plurality of enclosed spaces, means including a thermostat responsive to the temperature of the said tempered air and set to function at a predetermined temperature for controlling the effectiveness of said primary air heater, a heat radiator for radiating heat directly into the several enclosed spaces as a group, means including a thermostat responsive to a temperature factor common to all said spaces of said group and set to function at a predetermined temperature to control the effectiveness of the said heat radiator, a booster heater associated with each enclosed space for adding heat to the tempered air immediately prior to its delivery into its associated enclosed space, means including separate thermostats associated with each of the several enclosed spaces and responsive to the temperature of its associated space for controlling the effectiveness of its associated booster heater, electrical heaters for the several thermostats for controlling said booster heaters, energizing circuits therefor connected through individual variable resistors for varying the volume of heat applied to the thermostats, an electrical heater for the thermostat which controls said heat radiator, an energizing circuit therefor, and impedance connections leading from each of the variable heater circuits associated with the booster heater control thermostats and connected into the energizing circuit for the electrical heater for the heat radiator control thermostat so as to automatically adjust the temperature setting of the heat radiator control thermostat in relation to the average temperature settings of the booster heater control thermostats.

3. A temperature control system as defined in claim 2, characterized in that each of the said individual variable resistors is a manually operable potentiometer located in each of the several enclosed spaces for operation by the occupant of such space.

4. A temperature control system vas defined in claim 2 in which each of said spaces includes a side Wall having inner and outer panels and the said heat radiator is postioned between said panels and the heat radiator control thermostat 10 responds to the temperature of the inner panel of the side wall.

5. A temperature control system as defined in claim 2 inwhich each impedance connection includes a metered resistor havinga predetermined maximum value when the variable resistance associated therewith is least effective.

6. A temperature control system as defined in claim 5 in which the several metered resistors are tapped into parallel heater circuits and into a bus connector connected in the circuit for energizing theheater of the heat radiator control thermostat.

7. In combination with apparatus, including an air cooling element, for supplying tempered air to a plurality of enclosed spaces, means including a thermostat responsive to the temperature of the said tempered air and set to function at a predetermined temperature for controlling the effectiveness of said air cooling element, individual apparatus associated with the individual spaces for altering the temperature of the air supply immediately before its delivery into an individual space, means including separate thermostats associated with each of the several enclosed spaces and responsive to the temperature of its associated space for controlling the effectiveness of its associated individual temperature altering apparatus, electrical heaters for the several thermostats for controlling said individual temperature altering apparatus, energizing circuits therefor connected through individual variable resistors for varying the volume of heat applied to the thermostats, an electrical heater for the thermostat lwhich controls the said air cooling element, an energizing circuit therefor, and impedance connections leading from each of the variable heater circuits associated with the individual temperature altering apparatus control thermostats and connected into the energizing circuit for the electrical heater of the cooling element control thermostat so as to proportionately adjust the temperature setting of the cooling element control thermostat in relation to the average temperature settings of the several thermostats associated with each of the several enaltering apparatus.

8. A temperature control system as defined in claim 7, characterized in that the individual temperature altering apparatuses are air heaters for raising the temperature of the previously cooled air and the manually operable means for varying the temperature settings of the separate space thermostats is a potentiometer located in each of the several enclosed spaces for operation by the occupant of such space.

9. A temperature control system as dened in claim 8 in which each impedance connection includes a metered resistor having a predetermined maximum value when the variable resistance associated therewith is least effective.

10. A temperature control system as defined in claim 9 in which the several metered resistors are tapped into parallel heater circuits and into a bus connector connected in the circuit for energizing the heater of said air cooling element control thermostat.

TIMOTHY J. LEHANE.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 2,234,288 Smith et al Mar. 11, 1941 2,476,199 Lehane et al July 12, 1949 2,613,919 Russell et al Oct. 14, 1952 

